A wrapping machine as described in U.S. Pat. Nos. 3,791,100, 5,203,144 and 5,203,146, generally comprises:
a first conveyor, supporting the articles to be wrapped and feeding them one by one to a second conveyor; PA1 a second wrapping phase conveyor having an inlet end, an outlet end, and an upper surface between the inlet and outlet ends, this upper surface supporting and conveying articles while they are wrapped in succession; PA1 means for feeding single pieces of wrapping material, in succession, to the wrapping phase conveyor, placing the leading extremity of each piece on the upper surface of the wrapping phase conveyor, at the inlet end thereof; PA1 wrapping means comprising an endless conveyor carrying at least one wrapping bar along a path surrounding the above mentioned wrapping phase conveyor, and carrying the heat-shrinkable set the above mentioned heat-shrinkable wrapping pieces over and in front of each article then placing the rear extremity of the piece in a region between the second conveyor and the upstream end of a third receiving conveyor; PA1 a third receiving conveyor, for receiving and supporting the partially wrapped articles, aimed placing the rear extremity of the wrapping material piece under the leading extremity of the same wrapping material piece; and PA1 synchronising means, designed to set in proper timed relation the first conveyor, the first conveyor, the motion of the above mentioned second conveyor, the means for feeding the wrapping material, the endless transport means and the related wrapping bar, and the motion of the third receiving conveyor.
These machines, made as explained hitherto, are affected by several drawbacks as far as the transport of the wrapping material piece by the wrapping bar endless transport means is concerned.